Risk minimization as a novel optimization objective for fusion power plant design in FUSE

In this work, we extend FUSE, General Atomics’ framework for integrated fusion pilot plant design, to include a risk metric as a new dimension for multi-objective optimization. As fusion power plant design studies progress toward the pursuit of commercial viability, increased attention has been paid to the study of costing for comparative design. In optimizing design choices solely based on minimal cost, however, the overall risk associated to constructing the selected design can go unchecked. Thus, there is a need to quantify both the technology- and plasma-related risks associated to a particular design simultaneously with cost in order to assess the tradeoffs. Multi-objective optimization studies conducted using FUSE have previously sought to minimize normalized beta as a proxy for plasma stability-related risk, in addition to minimizing capital cost. In the new risk framework, technology risks, such as the selection of a particular superconducting magnet or blanket material, or source of external heating and current drive, are given as an adjustment to the direct capital cost informed by the component’s technology readiness level in a fusion environment. Plasma risks, such as operation in positive or negative triangularity, are given as an adjustment to the plant’s levelized cost of electricity in $/kWh. Resulting design spaces from optimization for minimized technology risk versus minimized plasma risk are shown and compared in terms of their resulting costs, sizes, and plasma parameters.